In a variety of fields, a need often arises to physically separate two liquids. This separation is facilitated when the liquids have different densities. When a mixture is comprised of two liquids of different densities, the force of gravity encourages the higher density fluid to settle near the bottom of the mixture while the lower density fluid generally rests on top of the higher density fluid. As such, the two liquids often separate into two substantially distinct layers. An example of such a process occurs when a liquid hydrocarbon such as oil is mixed with water.
Since liquid oil generally has a lower density than liquid water, when the two are mixed or otherwise come into contact, the liquid oil generally rises within the mixture as the higher density water settles towards the bottom of the oil-water mixture. When a steady state environment has been established, the liquid oil generally forms a layer resting on top of the water.
In the environment, the presence of oil in water, particularly on the surface of a body of water, can have a devastating impact on the environment. As experience has shown, the oil can easily kill both fish and other aquatic animals, upsetting the delicate ecological balance of nature. In addition to constituting a fire hazard, the oil makes the water unfit for human consumption. Unrecovered, the economic loss of the oil may be substantial.
Depending on the particular hydrocarbon involved, little time is generally available for removing the oil from the water surface before the oil sinks to the ecological environment below the water surface, or pollutes nearby land. Heretofore, there has not existed a simple yet efficient means for collecting the oil during the relatively short period of time before ecological damage occurs. In addition, there has not existed a simple yet efficient fluid recovery device which can recover a fluid which is on fire.
Moreover, there has not been available such an efficient oil collecting device which could function in a variety of turbulent water environments. In such turbulent environments, wind and waves would often disrupt and displace previously known oil skimmers, thereby reducing the amount of oil collected and increasing the time required to collect the oil.
The prior art devices which have attempted to remove oil off of the surface of water have been generally inefficient and difficult to manufacture and operate. For example, U.S. Pat. No. 3,534,859 discloses a device 10 for removing oil floating on water. Device 10 is shown comprising an inner flotation member 12, an outer stabilizing and buoyancy member 14, and a plurality at rib members 16 interconnecting members 12 and 14. As can be seen in FIG. 2 of U.S. Pat. No. 3,534,859, oil layer 26 flows, as a result of gravity, into the interior of device 10 for collection through hose 44.
However, this device has a number of disadvantages. The collection of oil layer 26 is limited by the gravity flow rate of the oil into the apparatus. In addition, the height of inner flotation member 12 is regulated by adjusting the volume of air and water within flotation member 12, a burdensome and often inaccurate method. Furthermore, the use of ring-shaped outer stabilizing member 14 and ring-shaped inner flotation member 12 allows for water and debris to enter tube 44 and reduce the efficiency of the apparatus. For these and other numerous reasons, device 10 often does not meet the critical needs associated with oil recovery.
Consequently, heretofore, there has not been available in the industry a convenient, simple, and efficient device for suctioning a fluid located on top of another fluid. In particular, such a device has not existed for suctioning oil off of a water surface. Because of the massive amounts of oil that sometimes are deposited on water surfaces, there has not been available heretofore a simple device for quickly removing the oil before significant ecological damage has occurred. Moreover, heretofore there has not been available an oil suctioning apparatus which can be easily adjusted to compensate for different oil layer thicknesses.